The present invention relates to a rolling bearing device for vehicles used for, for example, an anti-lock brake system (ABS).
On a motor vehicle mounted with an anti-lock brake system (ABS), there is often used a rolling bearing device for vehicles in which a magnetic sensor is attached to a roller bearing rotatably supporting a driven wheel. The rolling bearing device for vehicles is mounted with a cover to protect a ring-shaped magnetized element (magnetized pulser ring) arranged so as to face to the magnetic sensor and to prevent muddy water from adhering to the magnetized pulser ring. As this cover, a nonmagnetic material is used so that the magnetized pulser ring can be protected and a change in magnetism of the magnetized pulser ring can be detected with high accuracy (refer to Japanese Patent Laid-Open No. 2004-198378).
A problem with the conventional rolling bearing device for vehicles is that even if a nonmagnetic material is used as the cover, the cover is magnetized when being pressed, and the residual magnetism exerts an adverse influence on the output waveform of magnetic sensor with respect to the change in magnetism of the magnetized pulser ring, resulting in the degradation in detection accuracy of magnetic sensor.